1. Field of the Invention
The present invention relates to a substituted pyrazole derivative useful as a herbicide and to a herbicide composition containing the substituted pyrazole derivative as an active ingredient. More particularly, the invention relates to a herbicide composition containing as an active ingredient a substituted pyrazole derivative represented by the following formula (I), which has a wide herbicidal spectrum, can be applied in a small dose, shows sufficient safety to certain important crops and is useful in fields of chemical industry and agriculture, particularly in a field of production of agricultural chemicals. 
2. Description of the Prior Art
In cultivation of important crops such as wheat, corn, soybean and rice, a great number of herbicides are employed at present. However, there are many species of weeds to be controlled, and emergence of the weeds lasts over a long period of time. Therefore, most of the herbicides have a problem that their herbicidal activity, herbicidal spectrum, residual effectiveness and crop selectivity are not always satisfactory.
On this account, development of a novel herbicide composition exerting an excellent herbicidal effect even when applied in a small dose, having a wide herbicidal spectrum and showing sufficient safety to certain important crops has been desired.
Under such circumstances as mentioned above, the present inventors have made various studies, and as a result, they have found that a substituted pyrazole derivative represented by the above formula (I) has a wide herbicidal spectrum and exerts an excellent herbicidal effect and that a herbicide composition containing the substituted pyrazole derivative as an active ingredient exerts an excellent herbicidal effect even when it is applied in a small dose and shows sufficient safety to some importance crops. Based on the finding, the present invention has been accomplished.
In addition, it is also known that substituted pyrazole derivatives have fungicidal activity, and processes for synthesizing such derivatives are described in Japanese Patent Laid-Open Publication No. 168063/1998 and European Patent No. 0945437A1.
In the above publications, however, there is no description of the herbicidal activity of the substituted pyrazole derivatives at all, and also in the prior art, it has not been found that the substituted pyrazole has herbicidal activity.
It is an object of the present invention to provide a herbicide composition containing a substituted pyrazole derivative represented by the following formula (I) as an active ingredient, namely, a herbicide composition having a wide herbicidal spectrum, exerting an excellent herbicidal effect even when applied in a small dose and showing sufficient safety to some important crops.
The summary of the present invention is as follows.
(1) The herbicide composition according to the invention contains, as an active ingredient, one or more substituted pyrazole derivatives represented by the following formula (1): 
wherein X is R1OOC, R1HNOC, R1R1NOC, a cyano group or a 5-membered or 6-membered aromatic heterocyclic group,
W is an alkylene group of 1 to 3 carbon atoms or NR1,
R is a lower alkyl group of 1 to 4 carbon atoms or a lower haloalkyl group of 1 to 4 carbon atoms,
A, B and D may be the same or different and are each a hydrogen atom, a halogen atom or a group selected from the group consisting of R1, R1O, R1S, R1SO, R1SO2, (R1)2N, R1OOC, R1OR2, R1ONxe2x95x90CH, a cyano group, a nitro group, a lower alkenyl group of 2 to 4 carbon atoms, a lower alkynyl group of 2 to 4 carbon atoms, a cycloalkyl group of 3 to 7 carbon atoms, Ph, PhCH2, PhO, PhCH2O, PhOR2, PhS, PhCH2S, PhSR2, PhCH2ONxe2x95x90CH, Naph and Het, with the proviso that there is no case where A, B and D are hydrogen atoms at the same time and there is no case where A, B and D are aromatic groups or aromatic heterocyclic groups at the same time,
R1 is a lower alkyl group of 1 to 4 carbon atoms or a lower haloalkyl group of 1 to 4 carbon atoms,
R2 is a lower alkylene group of 1 to 4 carbon atoms,
Ph is an unsubstituted or substituted phenyl group,
Naph is an unsubstituted or substituted naphthyl group, and
Het is an unsubstituted or substituted, 5-membered or 6-membered aromatic heterocyclic group.
(2) The herbicide composition according to the invention preferably contains as an active ingredient a substituted pyrazole derivative of the formula (I) wherein X is R1OOC, W is a methylene group or an ethylene group, R is a methyl group, A and B are each a hydrogen atom, a halogen atom, R1 or R1S, and D is an unsubstituted or substituted phenyl group (R1 is a lower alkyl group of 1 to 4 carbon atoms or a lower haloalkyl group of 1 to 4 carbon atoms).
(3) The substituted pyrazole derivative contained in the herbicide composition described in the above (1) is preferably at least one compound selected from the group consisting of the compounds No. 1 to 47 enumerated in the later-described Table 1.
(4) The substituted pyrazole derivative contained in the herbicide composition described in the above (1) is more preferably a substituted pyrazole derivative represented by the formula (I): 
wherein X is R1OOC, R1HNOC or R1R1NOC,
W is a lower alkylene group of 1 to 3 carbon atoms,
R is a lower alkyl group of 1 to 4 carbon atoms,
A and B are each a hydrogen atom, a halogen atom, R1 or R1S,
D is a phenyl group, a naphthyl group or a 5-membered or 6-membered aromatic heterocyclic group (these groups may be unsubstituted or may have a substituent), and
R1 is a lower alkyl group of 1 to 4 carbon atoms or a lower haloalkyl group of 1 to 4 carbon atoms.